Sheet-metal joint



May 15, 192s.

R. B. BRANDL SHEET METAL JOINT Filed Sept. 27. 1926 gyn/vento@ neil Patented May 15, 192s.A

UNITED STATES PATENT OFFICE.

ROBERT B. BRANDL, F ST. PAUL, MINNESOTA.

SHEET-METAL JOINT.

Application led September 27, 1926. Serial No. 138,030.

elements and should the building, in the construction' of which the joint is employed, l@ contain valuable merchandise or machinery,

it is desirable -to have the joint inaccessible tor separation on the outer side thereof.

An object of the present invention is tov make an interlocking joint for the edges oi sheet metal plates, said joint being formed with a covering thereover and having fastening means acting intermediate the inner and outer surfaces of said joint to draw the parts into position to interlock lthe component parts of said joint.

Another object is to join the edges of -a pair oli sheet met-al plates by bending an edge of one metal plate to 'torni a channel vwith an odset portion therein; and by bending the other ot said edges to interlockingly engage said oiiset portion of the rst plate. ln order to attain these object's there is provided, in accordance with one feature oi the invention, a sheet ot metal having an Vedgethereot hentto form a ridge with theedges oi'i said ridge bent inwardly; and a second sheet oit metal having an edge thereof folded upon itself so as'to engage a portion of the hrst mentioned sheet to interas loclr therewith, the interlocking portions of said sheets being completely covered by said ridge to form a weather tight and comparatively inaccessible joint.

'llhese and other eatures of the invention,

do not specihcally mentioned, will be more.

fully brought out in the following description and the accompanying drawings, wherein:

Fig. l, is a view in perspective of a pair no ol sheet metal plates joined together in accordance with the preselnt invention.

Figure 2, is a sectional view transversely ot the joint with the parts in interlocke4 osition, but @o astening means.,

Figure 3, is a. view similar to F1gure 2, showing the parts in fully interlocked position and crimped by the fastening means. Figure 4, is a. view similar to Figure 2,

vents the bracket before being crimped by theshowing a modified form of clamping de- Figure 5, is a view in perspective of a.

clamping element used in 'Securing the joint in place; and J Figure 6, is a view similar to Figure 2,

showing a modified form of joint.

Referring to the drawmgs 1n detail, a sheet l of metal is bent back upon itself for a short distance and then angulaily outward as at 4. On the line 5 the sheet is again bent angularly downward to the point 6, where it is bent inwardly. pointit extends' parallel to the original sheet l. *for a short distance, where it is again bent back upon litself as at 7 and terminates in the present illustration directly below the edge 6. A second sheet 2 has its edge bent upwardly and back upon itself as at 8 so as to receive the portion 7 therein.

ln 'large sheet metal buildings, and in granaries, where additional strength is required, angle iron supports 3 may be used to brace `the walls vertically, although such From this additional bracing is not necessary in the construction of small buildings and those in which there is no internal pressureagainst the walls, since the ridge formed by the folding olf the sheet l ,resists transverse bending of the sheets. l

In ang the plates to, the vertical angle irons, brackets B, having bolts 9 passing through the opening in said bracket, as shown in Figures 1 to 3, inclusive, are inserted in the interior of the ridge ormed by the bending of sheet l with an end oi the bracket overhanging the inwardly turned edge of the plate 2, The bolts are then inserted through holes in and the nuts are screwed down. yThe engagement of the overhanging end of the bracket B with thel edge of the plate 2, prefrom turning while the nuts 1l .are being drawn into place. The heads of the bolts are retained in a channel 1() in thelbracket `B which prevents the bolts from turning, during the tightening of the In constructions where the vertical angle -iron braces are not required, bracket B may the angle iron 3y the inner bracket B bef.

having a width suii'iciently greater than the width of the channel l() to keep the nut 1l from entering the channel bein(Ir provided to permitthe nut to be screwed own into position.

llt will be noted, especially in Figure 1, that the joint is entirely shielded by the ridge, and that the nuts holding the plates together are inaccessible from the outer side of the joint. 'lhis prevents removal of the fastening means toI release the joint for separation, as is possible in construction wherein the fastening means are accessible from the outer side of the joint. Another advantage lies in the complete shielding of the fastening means from the Weather. The metal sheets used in the construction of sheet metal buildings are usually of sheet steel galvanized or otherwise coated to resist rust and corrosion. ln a joint .of an ordinary type, where the sheets are punched to receive bolts for fastening, the inner edge of the punched out hole has no galvanizing or protective coating. As a result, rust and corrosion are free to act on the edges of these holes, and, as the corrosion proceeds beyond the area. occupied by the fastening means, releases the joint for separation.

'lhe present joint is entirely weather tight and may be considered asy complete in the form shown in Figure 2, but additional strength and rigidity may be obtained by drawing the parts into the position shown in Figure 3, by further screwing down the nut 11; 'lhe joint as illustrated in Figure 2 might be employed to advantage where the building was of a temporary nature and was intended to be taken down and moved,

whereas, the joint. as drawn down to the position shown in Figure 3 would be preferable for a building of a more or less permanent character.. y

A. modied form of joint is shown in Figure 6. ln this form both edges of a pair of sheets forming the joint are turned back upon themselves as at 16 and a ridge or closure member C for covering the joint is formed of a strip of sheet metal bent longitudinally thereof as at 17 and having tlie edges turned in as at 18 to engage the folded edges of the sheets 15. A clamp member similar to the one shown in the other gures extends beyond the ends of the folded edges of the sheets forming the joint and rests upon the bent in portions of the ridge member C; An angle iron brace member 19 is positioned interiorly of the joint as in Figures 1 to 3, and a bolt 20 draws the parts into compression to hold them firmly in place. A. clamp member may be used interiorly offthis type of joint instead of the angle iron 19, the same as with the type of joint illustrated -in Figure 4c in cases where extraordinary vertical rigidity is not required.

ll claim:

A. joint of the character described, comprising sheets of material, each having an edge thereof bent backwardly upon itself, a ridge over said inwardly bent edges, a portion of said rid e being bent inwardly to lie interiorly of said ridge, clamp means positioned interiorly of said ridge and having an end thereof bent downwardly to engage the inwardly bent portion of said ridge and the bent edge of each of the sheets, reinforcing means positioned against the inner side of said joint and means connecting lthe' clamp means and the reinforcing means to draw them together and grip the joined edges of said sheets in interlocking relation with each other.

ln testimony whereof l affix my signature.

ROJBFRT QB. BRANDL. 

